Coded Acoustic Microscopy to Study Wood Mechanics and Development

We have developed a coded excitation scanning acoustic microscope (CESAM) that operates in range of 0.1 to 1 GHz. We used a focusing transducer with 375 MHz central frequency to image two different tree species (birch and hybrid aspen) at different stem height to study their micromechanical difference. The method was able to capture the fresh wood anatomy with cellular resolution. A full stem section scan revealed the heterogeneity of micromechanical properties throughout tissues, and highlighted the higher stiffness of the phloem fibers compared to other vascular cells. This demonstrates the applicability of the method for plant developmental biology.